When a navy SEAL tells you to get wet, you’d better soak yourself real good. That was a lesson the U.S. Olympic sailing team learned the hard way last March during a surprise training session with the SEALs, who ordered the athletes into a frigid Colorado Springs lake. Since it was about 40F outside, some sailors didn’t exactly charge into the water like summer campers–or even dunk their heads. When they returned to shore, teeth chattering, a SEAL asked Zach Railey, a silver medalist in Beijing, a question: “Does wet hair move?” No, Railey replied. The SEAL blew on one of Railey’s female teammates’ dry ponytail. It wisped. So the SEALs marched the team back into the drink to freeze their asses off some more.

If the U.S. sailors collect medals in London, they can give some thanks to the SEALs. Over the past two years, the killer elite unit has put eight Olympic teams through the kind of agonizing trials a SEAL encounters in BUD/S (basic underwater demolition/SEAL) classes. It’s logical that athletes in endurance sports such as cycling and rowing would undergo a SEAL initiation, but the matchup of Special Ops and sailing–with its soft, country-club image–seems less intuitive. In truth, though, Olympic-level sailors need amazing dexterity and the ability to make critical decisions in changing conditions in order to guide dinghies through wind and rough waves. “No matter what the sport is, you want to take athletes out of their comfort zone,” says Wendy Borlabi, a psychologist with the United States Olympic Committee who forged the partnership with the SEALs after she joined the USOC in early 2010. “The SEALs are a natural fit.”

Likewise, many Olympians may be a natural fit for the SEALs, which is why the Navy sees these training drills as a recruiting tool worth the taxpayer investment. “I’d be lying if I said we weren’t interested in our community getting some awareness from these programs,” says Rob Stella, chief special-warfare operator for the SEALs. (Since women can’t become SEALs, the Navy hopes they talk up the experience to their male peers.) Stella says four Olympians who worked out with the SEALs have made plans to sign up after the 2012 Games. (Swimmer Larsen Jensen, a silver medalist in Athens, enlisted after winning bronze at the Beijing Olympics, though he did not train with the SEALs beforehand.)

SEAL sessions usually begin in a classroom setting with a lesson on mental toughness that stresses visualization, setting microgoals–in which you focus intensely on the task in front of you–with positive self-talk and breathing exercises that decrease anxiety. Then the SEALs deliver the pain. The officers drilled 42 sailors the first day; only 18 finished all the tasks. Some were sobbing. “Everything they do is pretty much the worst thing they can make us do,” says Lauren Crandall, captain of the U.S. field-hockey team, which also worked out with the SEALs. “It’s just flipping tires, carrying logs, doing more push-ups, doing more push-ups, doing more push-ups. Then if you lose, you do more push-ups.”

The SEALs directed the field-hockey team to jump into the cold Pacific Ocean, then roll in the sand, a drill known not so fondly as the sugar cookie. At a follow-up session at the inland Olympic-training center near San Diego, the players relaxed a bit. At least we’ll avoid the ocean, the women thought. Instead, the SEALs took the ocean to them. At a 5 a.m. session, the players spotted boats lined up on a beach-volleyball court. “They filled the boats up with water,” says Crandall. “Chief Stella–bless his heart–was nice enough to buy $100 worth of ice.” Cookie time.

Stella gives Crandall and her teammates high marks. “These field-hockey girls, they’re like the average woman. They’re petite. They’re athletic, but they don’t look like some kind of power lifters,” he says. “But they were crushing it.” It included a drill in which six or seven women joined together to lift a 230-lb. log over their heads and run a set of relay races. Stella has worked out some college-football studs–he won’t name them–who could not carry out this task. One NFL prospect quit on him. Not the field-hockey players.

On another occasion, after 4 hours of punishment, Stella told the players to run 2,500 ft. up the San Miguel Mountain near San Diego. When they reached the top, the athletes feared they’d have to sprint back down. Instead, the SEALs rewarded the women with sandwiches and sports drinks. The group rode down the mountain in vans. “It was a little ‘attaboy’ at the end there,” says Stella. “We always finish on a high note.”

That high note was sustained at last October’s Pan Am Games, where the U.S. field-hockey team upset the world’s top-ranked squad at the time–Argentina–4-2 to qualify for London. Stella will give the players one more pep talk before the Olympics and will spare them the logs, ice and sugar cookies. The military message has stuck. “When you’re tired and it’s the last few minutes of the game and your team needs you to score because that’s your job, you just need to put on this extra game face,” says Katie O’Donnell, a field-hockey striker. And you can, she adds, “because you’ve done SEALs. You say, I’ve done it before. Nothing is harder.”